What is a period?

A period is part of a women’s menstrual cycle, the time from the first day of a woman’s period to the day before her next period. We are born with all our eggs and they are stored in our ovaries (between 1 and 2 million!) but only a fraction are actually released during our lifestyle. Most women start their periods between the age of 10 and 14 and at least one of these eggs will ripen and released from your ovary during each cycle.

After it is released the egg travels down your fallopian tube to your uterus. If this egg is fertilised by a man’s sperm then it will implant in the uterus and go on to grow into a baby. When fertilisation doesn’t take place, the egg is flushed along the lining of the uterus and that’s when a period occurs.


Periods usually last around three to seven days, and women lose approx three to five tablespoons of blood during that time. The first day of a woman’s period is considered to be day one of the menstrual cycle and an average cycle lasts between 28 and 30 days.

Our hormones

The menstrual cycle is a complex process, controlled by our hormones, and it may surprise many to know that it actually starts in the brain and not in the reproductive organs.

Gonadotrophin- releasing hormone (GnRh) stimulates your body to make and release Follicle Stimulating Hormone (FSH) and Luteinising Hormone (LH) from the hypothalamus in the brain.

– FSH is produced in the pituitary gland (also in the brain) and causes the eggs to ripen ready to be released.

– LH is also released from the pituitary gland and stimulates your ovaries to release the eggs.

Oestrogen (produced in the ovaries) causes eggs to mature and thickens the lining of the womb.

Progesterone prepares the body to receive and nourish a fertilised egg. If implantation does not occur, levels drop (along with oestrogen levels) and menstruation occurs. Your menstrual cycle will then start all over again.

The menstrual cycle & health

what is a period 1Cycles vary from woman to woman and can be as short as 22 days and as long as 36. As we age and move towards the menopausal years (51 is the average age for the menopause in the UK), periods can be very sporadic and not arrive for 3-4 months at a time. When a woman’s periods stop for a year or more that is when she is considered to have gone through the menopause.

Some women struggle with health issues related to the menstrual cycle which include painful, heavy or irregular periods, absent periods and premenstrual syndrome (PMS).

These can be caused by many factors including:

– A change of contraception
– An imbalance of the hormones oestrogen and progesterone
– Excessive weight loss or gain
– Stress; caused by physical, mental or emotional factors
– Health conditions including thyroid issues, polycystic ovarian syndrome or endometriosis

It is always important to both embrace and understand your body, that way we always have a better chance of getting the best out of it. Feel free to contact me with queries or comments.

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